By: Brigitte Osterath

Like people, rats are ticklish. Now, by implanting electrodes in the brains of these laboratory workhorses, researchers have identified the brain region that seems to drive the trait — an insight that could illuminate the origins of ticklishness in people.

The work, published in the 11 November issue of Science¹, also reveals that rats’ susceptibility to tickling is affected by mood, rather like in people. Separate from the study, the researchers say they have found that rats are ticklish in similar places to people — on their tummies and back paws, but not on their backs or on their front paws.

In the late 1990s, neuroscientist Jaak Panksepp, who was then of the Bowling Green State University in Ohio, discovered that rats make ultrasonic ‘chirps’ when being tickled and while playing², which may be similar to human laughter.

Several other animals are ticklish, including dogs and chimps, but rats seem particularly so, and are easy to handle in the lab. So neuroscientists Michael Brecht and Shimpei Ishiyama of the Bernstein Center for Computational Neuroscience in Berlin decided to use the animals to probe what is going on in the brain.

Read Full Story: http://www.nature.com/news/playful-rats-reveal-brain-region-that-drives-ticklishness-1.20973